Headphone



July 4, 1944. R. s. PlTKlN, JR

HEADPHONE Fi ed March 22, 1943 2 Sheets-Sheet 1 July 4, 1944. k. s. PlTKIN, JR

HEADPHONE Filed March 22, 1945 2 Sheets-Sheet 2 Patented July 4, 1944 UNITED STATES PATENT 'OFFICE HEADPHONE Roy S. mun, In, mm, Minn.

Application March 22. 194:, Serial No. 480,013

1 Claims. (Cl. 179-156) This invention relates to improvements in headphones for use in communication systems. These headphones are particularly advantageous when used in connection with communication systems where there is a high ambient noise level, such as, for instance, in modern warfare equipment, i. e., tanks, trucks, airplane control rooms, torpedo boats and the like, where communication is essential for successful operation thereof.

The main objects of this invention are to provide a headphone which will increase the intelligibility' of intercommunication reception; to provide a headphone so constructed and designed as to substantially prevent outside noises from interfering with the signals emanating from the phones; to provide a headphone of this character which may be worn for extended periods of tim without discomfort to the wearer; to provide a headphone of this character which is adapted to be used interchangeably with a headband or secured to the flap of a flexible helmet of cloth or the like to provide a set of headphones of this character which is so compact in construction that a. metal or fiber helmet may be worn over the headphone and band without discomfort to the wearer; to provide a headphone of this character which has a flexible cable extending forwardly therefrom, arranged to hold a lip microphone; to provide. a-headphone of this character wherein a'fle'xibleresilient sound duct .is sei ured to the sound emission port of the phone unit, the free end of which is arranged to abut against the outer walls of the auditory canal and direct communication signals directly from the phcne unit to the earcanal; to provide a headphone of this character which is provided with cushioning means to increase the comfort thereof when in use and simultaneously to act as a seal to prevent outside noises from interfering with the signals emanating from the phone unit; and to provide a headphone of this character which is relatively simple in construction and inexpensive to manufacture.

An illustrative embodiment of this invention is shown in the accompanying drawings in which;

Figure 1 is a perspective view of my improved headphone.

Fig. 2 is a vertical cross-sectional view taken on the line 22 of Fig. 1.

Fig. 3 is a vertical sectional view similar to the view shown in Fig. 2 but with the device applied to the head of a user. I

Fig. 4 is a horizontal view taken on the line 4-4 of Fig. 3, with parts of the construction omitted.

Fig. 5 is a perspective view of the microphone holder shown detached from the headphone.

Fig. 6 is an elevational view showing the headphone unit attached to a flexible helmet, such as an aviator's helmet.

Fig. 7 is an elevational view similar to Fig. 6 but showing the headband attached to the phone unit.

Referring in detail to the drawings, my improved headphone comprises an oval-shaped cup I, preferably steel, which is inserted in a soft rubber-like envelope 2. The envelope 2 is preferably constructed from a synthetic rubberlike plastic formed by polymerization of chloroprene and commercially known as neoprene.

The peripheral edges of the envelope 2 are bulbous in form, similar to an enlarged bead,

as shown at 3, for the purpose oi. housing the flanged edge I of the cup I and also to form a cushion for the headphone. The central portion of cup I is cutaway and provided with an inwardly turned integrally formed flange 4 having a shoulder 5. A U-shaped member 6 is arranged to seat on the shoulder 5 and act as a.

retainer housing for the phone unit I. The envelope 2 is cut away centrally as at 2' so as to seat in the U-shaped member 6 when the phone unit I is placed in positiontherein and provide an opening through which the flange 8 of the sound emission port 8' of the phone unit I, may extend.

A sound duct 9 of bulbous form, preferably made of rubber, is arranged to frictionally seat on the flange 8 of the phone unit I. The duct 9 is provided with flutes I 0 so as to render the duct very pliable and flexible, whereby the duct 9 may be readily compressed and returned to normal position upon release of any pressure exerted thereon.

The duct 9 is also provided with a flexible tube II which may be integrally formed with the duct 8 and is positioned centrally within the duct 9 as shown. The duct 9 is also provided with an opening l2 for the ready emission of signals coming from the phone unit I. The free end of tube II is positioned to direct the signals to the open- A cable 13 containing the lead-in wires for the phone unit 7 and the phone unit I itself are held in position on the'headphone by a cable clamp and cover plate I4. The cover plate I! is secured to the headphone by means of the set screw 15 which is threaded into the internally threaded boss I5 integrally secured to the inner face of the cup I.

In order to prevent moisture or water from entering the phone unit and further to help make the headphone soundproof, I have found it expedient to interpose a cushioning rubberlike washer l6, preferably made from neoprene, between the cover plate ll and the phone unit I, so that the same will cover the phone unit 1, and the area of the headphone next adjacent the phone unit I. 3

The cover plate II is also provided with a pair of upstanding ears I! and I8 which are arranged to receive the pintles I! of the yoke 20 of the headband 2|. The headband 2| comprises a pair of arcuate-shaped flat springs 22 and 22 lying face to face and enclosed within a stiff canvas belting material which completely envelops the two springs. As shown the end of the spring 22 is secured to the yoke 20 which supports headphone A, while one of the springs 23 is secured to the other yoke (not shown) for holding the headphone B.

- As shown in Figure 1, the cables I2 and I! are joined together in junction unit .24. The lead-in wires contained in the cables l3 and ii are joined together in this junction unit 2| and form a single cable 25. A plug 26 is attached to the end thereof. Usually in this type of. headphone equipment a transformer 21 is interposed somewhere in the line between the plug 26 and individual phone units '5. To prevent the transformer '2? from exerting a pull on the headphones, a clip 28 is usually provided around the member 24 which is attached to the garment of the user by any suitable means, whereby the weight of the transformer is alleviated.

It will readily be apparent from Figs. 3 and 4 I that the shallow cup i will envelop the ear of the user without exerting the slightest pressure thereon or deforming it in any manner. The

bulbous head 3 cushions the phone as a whole against the head and at the same time, in conpart of the headphones. As shownespecially in Figs. 1 and 5 this apparatus consists of an arouate-shaped plate 29 having a pair of spaced upenvelope 2 and is held in position therebetween junction with the envelope 2, acts as a means to exclude extraneous noise from the interior of cup i. The duct 9, positioned in the interior of the cup 8, molds itself to the ear contour and positions the opening Q2 of the duct directly at the opening of the ear canal, thereby forming a continuous channel between ports 8 of the phone. The flutes i0 allow for compressionof the duct, and as" will be apparent, a gentle constant pressure is always exerted thereby so as to form somewhat of an acoustic seal around the entrance of the ear canal of the wearer.

It will now be apparent that signals originating from the diaphragm of the phone unit will be guided directly into the ear canal and to the eardrum. Therefore, there is absolutely no chance for distort-ion of the signal.

In most of the equipment of the armored forces and in most airplanes where intra-communication is required because of the high noise levels within the equipments and airplanes, it is usually necessary to amplify the voice by means of loud speakers. To do this a microphone must be available. 7 The usual type of microphone employed is known as a "hand mike" which must be picked up with the hand in order to place the same adjacent the mouth, preparatory to speaking into it. This means that if the hands are busy performing other duties, such as directinfl or driving the vehicle, or manipulating one of the guns, one of the hands will have to be disengazed therefrom in order to use the microphone.

In order to circumvent this problem, I have designed a microphone which is or may when the set screw I5 is tightened.

Extending from plate 29 is a flexible conduit 32 to which a lip microphone 33 is secured to the distal end and the cable 34, containing lead-in. wires (not shown) is contained therein. One end of the lead-in wires in the cable 34 is secured to the microphone elements, not shown, and the other end is secured to the amplifier, not shown. As the conduit 32 is very flexible, it can readily be seen that the microphone may be adjusted to the lipsof the user, and never be handled, so that both hands of .the individual may be employed in performing his other duties, such as manning a gun, piloting the vehicle, etc.

Since the headphones are hat and compact, I

they may be worn underneath all types of helmets without discomfort. After the headphones v are-positioned on the head of the user, a helmet without either disturbing the headphones or interfering with the headphone performance. Figure 7 illustrates how readily the headband is adapted to be worn under a helmet.

As shown in Fig. 6, this improved headphone may readily be adapted and secured to an aviators helmet or a crash helmet by merely disengaging the headband, loosening the set screw 15 and inserting the ear flap 35 of the helmet between the envelope 2 and the cover plate Hi. Then by tightening the set screw i5 the earphone becomes pan of the helmet.

Another important feature flowing from this new design is the protection it affords the ears of the wearer. Any sudden forceful blow on the side of the head of the wearer of an ordinary type of headphone may cause serious injury to the ear as well as extreme discomfort to the wearer. In my headphone, I employ a hard metal, shallow cup i which envelops the ear, and the cup is provided with a perpendicular flange l' which is designed tolie in the same plane as the side of the head of the wearer. As I completely envelop the cup I with a rubberlike material 2 having a large bulbous cushioning bead 3, any forceful blow will be cushioned and the cartilage of the ear completely protected and unharmed.

Extraneous noises are sealed without the phone because of the cup I, envelope 2 and bead 3. However, if any noise does filter through-the same it'is apparent that such noise is greatly diminished in volume,'once inside the cup i, and in order to interfere with the signal issuing from the phone unit, it must go through the walls of the sound duct, which is almost an uncertainty.

.Also, as the phone unit I is connected to the auditory canal by the sound duct 9, the volume of air between the phone unit diaphragm and the eardrum is kept at a minimum and therefore, there is no resonant cavity to jumble the signalwhen an airplane goes into a dive, the pilot usually experiences great pain in his ears due, it is believed, to the sudden changes in pressure. Since my improved headphones are provided he a with an acoustical seal (head 3) and a sound 'ginal edge of said cup, which together with the duct, (9) which also acts as a seal, these elements also act as a semi-efilcient air seal and cushion and lengthen the time of change in air pressures, thereby allowing the Eustachian tube to more readily equalize the changes in pressures.

It is to be understood that the phone unit is merely a receiver 1. e., a device which is connected to an amplifier and into which electrical impulses are transmitted, whereby the receiver translates the same into audible signals. The receiver usually comprises a magnet anda diaphragm positioned in a suitable housing.

It is to be understood that some of the details set forth may be altered or omitted without departing from the spirit of my invention as defined by the following claims.

I claim: I

1. A headphone comprising a shallow, rigid cup having an opening therein, a sound-proofing covering completely enclosing said cup, a resilient, soft hollow bulbous bead around the marginal edge of said cup, which together with the cup completely encloses the ear to acoustically seal said cup to the head, a phone unit rigidly carried by said cup, an elongated resilient, soft, longitudinally compressible sound duct, one end of said duct having an enlarged head thereon, the other end of said duct projecting through said opening in said cup and communicating with said phone unit, and the headed end adapted to abut and seat itself against the entrance of the auditory canal of the wearer without substantial penetration therein so as to acoustically seal the end thereof, said duct being suficiently flexible to accommodate itself to irregularities in the .walls surrounding said canal.

2. A head phone comprising a shallow, rigid cup having an opening therein, a resilient, soft hollow bulbous bead around the marginal edge of said cup, which together with the cup com-'- pletely encloses the ear to acoustically seal said cup to the head, a phone unit rigidly carried by said cup, an elongated resilient, soft, longitudinally compressible sound duct, one end of said duct having an enlarged head thereon, the other end of said duct projecting through said opening in said cup and communicating with said phone unit, and the headed end adapted to abut and seat itself against the entrance of the auditory canal of the wearer without substantial penetration therein so as to acoustically seal the end thereof, said duct being suficiently flexible to accommodate itself to irregularities in the walls surrounding said canal.

3. A head phone comprising a shallow, rigid cup having an opening therein, a sound-proofing covering completely enclosing said cup, a resilient, soft, hollow bulbous head around the mar= cup completely encloses the ear to acoustically seal said cup to the head, a phone unit rigidly carried by saidcup, an elongated resilient, soft, longitudinally compressible sound'duct, one end of said duct having an enlarged head thereon of a diameter larger than the auditory canal of the wearer, the other end of said duct projecting through said opening in said cup and communicating with said phone unit, and the headed end adapted to abut and seat itself against the entrance of the auditory canal of the wearer without substantial penetration therein so as to acoustically seal the end thereof, said duct being sufficiently flexible to accommodate itself to irregularities in the wallssurrounding said canal.

4. A head phone comprising a' shallow, rigid cup having an opening therein, a sound-proofing covering completely enclosing said cup, a resilient, soft, hollow bulbous bead around the marginal edge of said cup which together with the cup completely'encloses the ear to acoustically seal said cup to the head, a phone unit rigidly carried by said cup, an elongated resilient, soft,

longitu J compressible sound duct provided with flutes, one end of said duct having an enlarged head thereon, the other end of said duct projecting through said opening in said cup and communicating with said phone unit, and the headed end adapted to abut and seat itself against the entrance of the auditory canal of the wearer without substantial penetration therein so as to acoustically seal the end thereof, said duct being sufiiciently flexible to accommodate itself to irregularities in the walls surrounding said canal.

5. A head phone comprising a shallow, rigid cup having anopening therein and being provided with an integral pocket, 2. phone unit carried in said pocket, 9. soft, resilient duct carried by said cup and projecting through said opening into the cup, one end of said duct communicating with the phone unit and the other end adapt ed to abut and seat itself against the mouth of the auditory canal so as toacoustically seal the end thereof, and a soft, hollow, bulbous bead around the marginal edge of said cup which together with the cup completely encloses the ear of the wearer and acoustically seals the cup to the head.

6. The device according to claim 1 wherein the cup is provided with a laterally extending flat marginal flange which is completely housed within said bulbous head.

'7. The device according to claim 2 wherein an auxiliary flexible sound conduit is disposed within said duct.

' BUY 8. Pl, JR, 

